Electrode air humidifier

ABSTRACT

An electrode air humidifier is provided. The electrodes are suspended in an inner container with water flow contact with the outer container through a pocket chamber, whereby pulsation is greatly reduced or prevented. It is further provided for separation of water drops in the steam and means are provided to reduce the wear of the electrodes by bringing the apparatus to a rapid stop when relatively little water is left in the apparatus.

United States Patent Rudstrom 1 Apr. 25, 1972 541 ELECTRODE AIRHUMIDIFIER 2,847,547 8/1958 Gordon ..219/275 2,843,891 7/1958 Fisher..21/119 [72] Inventor: Erik Rudstrom, Storgaten 22, Oslo, 1,

Norway Primary Examiner-A. Bartis Filed: Sept. 1970 Attorney-Young &Thompson 211 Appl. No.: 76,544 [571 ABSTRACT An electrode air humidifieris provided. The electrodes are suspended in an inner container withwater flow contact with [52] US. Cl ..2l9/284, 21/1 19, 219/273, theouter container through a pocket chamber, whereby 219/275 219/288 sationis greatly reduced or prevented. It is further provided [51] Int. Cl...HOSb 3/60 f Separation of water drops in the Steam and means are Fleldof Search a l 234-295, vided to reduce the wear of the electrodes bybringing the ap- 2 l 9/362; 21/1 17, l l9, 1 l8 paratus to a rapid stopwhen relatively little water is left in the apparatus. [56] ReferencesCited 20 Cl 4 Drawing Figures UNITED STATES PATENTS 2,763,765 9/1956 Duberstein et al ..2l9/289 X 34L l /0 I 6 J7 I x 46 g F? r77 5;; 52

l I I T 1 I l l 7 l 3 52 29 53 z/ a 4 z PATENTEDAPR 25 I972 3,659 O78SHEET 1 UF 2 ATTORNEYS PATENTED APR 2 5 m2 SHEET 2 GF 2 /PRIOR ART 5/INVENTOR [Fe/k eunsmo/w BY ATTORNEYS ELECTRODE AIR HUMIDIFIER Thepresent invention relates to air humidifiers of the type utilizingelectrodes for heating and evaporation of the water in a container, fordistribution into a room where the humidity is to be controlled.

The electrodes are preferably arranged in a small inner container whichis disposed in the actual water container and is in connection therewithby means of openings, so that a water flow contact exists between innercontainer and outer container. In this manner, the amount of water whichis to be heated and evaporated by the electrodes is restricted, andfresh water is continuously supplied from the outer container. Inconventional embodiments the inner container has an opening at the topend for discharge of steam and is provided with a plurality of openingsat the bottom end to receive water.

A disadvantage of the known types of electrode air humidifiers is thestrong pulsating rhythm at which the evaporation takes place.Immediately the water in the inner container or steam chamber reachesboiling point a steam pressure is generated which forces some of thewater back into outer container. If the dimension of the opening at thebottom of the pressure chamber is large in relation to the opening fordischarge of steam, the amount of water forced out of the steam chamberwill be so great that the current bridge between the electrodes isreduced and this naturally leads to decrease in boiling, with the resultthat the water again begins to penetrate the steam chamber. Inasmuch asthe temperature of the water entering the steam chamber is lower, theboiling stops until the electrodes have again been able to heat up thewater to boiling point. Thereafter the cycle repeats itself.

It is an object of the present invention to provide an electrode airhumidifier comprising measures for preventing pulsation or to reducesuch pulsation substantially.

Experiments have shown that when the water in the outer container has atemperature of between 80 and 90 C pulsation substantially iseliminated, since the above described cooling in the steam chamber isprevented. This discovery has been utilized in the invention and aconnection between the steam chamber and the outer container istherefore established via one or more pockets. The water in thesepockets will be maintained at a temperature of say between 80 and 90 Cand thus prevent pulsation, even though the water temperature in theouter container is lower.

In cases where the water contains a certain amount of lime, it isdesirable to achieve a moderate pulsation in order to prevent thecollection of lime in the pressure chamber.

It is thus an object of the invention to provide an electrode airhumidifier which permits a controlled pulsation. ln accordance with theinvention this is achieved by providing at least one opening which leadsdirectly from the outer container and into the steam chamber.

The water level in the outer container will gradually sink in time withthe consumption of water which is converted to steam and discharged intothe room. A curve showing the discharge of steam expressed in grams ofwater per time unit and drawn with amount of water distributed in gramsper time unit on the ordinate and with the time along the abscissa, willbe relatively steep to begin with, that is to say that the electrode airhumidifier reaches its maximum discharge amount relatively quickly. Thecurve then extends approximately parallel to the ordinate and then fallswith a relatively small incline, that is to say that at the terminationof the operation there will be a longer period of time wherein theelectrode air humidifier discharges only insignificant amounts of water.

It is an object of the invention to prevent this and to provide anelectrode air humidifier where the terminating extent of the curve issteeper.

In accordance with the invention this is achieved by disposing at thebottom of the water container a partition wall which extends around thesteam chamber. In this manner, a central, shallow well is formed intowhich the steam chamber projects. The opening or openings in the steamchamber which provide the water flow contact between outer container andsteam chamber are located in the part of the steam chamber whichprojects downwardly into the well. As soon as the level of water in theouter container sinks below the height of the partition wall, theelectrodes will be capable only of boiling away the water located in thewell, that is to say that the electrodes operate with a small amount ofwater and, therefore, despite the reduced electrode surface, are capableto evaporate the rest of the water in a shorter time and therebybringing the apparatus to a stop.

The boiling effect in the steam chamber is frequently violent, and dropsof water are thus readily entrained in the steam flowing out into theroom.

An aim of the invention is to provide an electrode air humidifier wheresuch entrainment of water drops is prevented to a substantial degree,and a special guide member is arranged in the steam outlet to thispurpose, the said guide member imparting a turbulent effect to the steamwhich facilitates the separation of water drops, and an auxiliarychamber is also arranged over the steam chamber wherein the steam isretarded before being released to the room.

The separated water drops are due to the whirling effect thrown outwardstowards the inner wall of a tube member which is connected with avertical tube which leads the water back to the electrode area. Thebottom opening of the tube has such a small diameter or is located insuch a way that steam bubbles from the electrodes cannot penetrate thetube or at least have a reduced penetrance capability. This causes acirculation of the water from the interior of the tube member and outinto the steam chamber.

It follows now a description of a preferred embodiment of the invention.

On the drawings,

FIG. I shows a section through an electrode air humidifier according tothe invention,

FIG. 2 shows a section along the line 11 II in FIG. 1,

FIG. 3 shows a section along the line III III in FIG. 1,

FIG. 4 shows a curve of the water discharge from the electrode airhumidifier.

In FIG. 1, the outer container of the electrode air humidifier isindicated by 1. At the base thereof, the outer container 1 is providedwith legs 2 and 3, with which the outer container rests upon thesurface, for example, the floor in a room wherein the electrode airhumidifier is placed. The outer chamber 1 is circular and symmetricabout the indicated main axis. The central portion 4 of the bottom ofthe outer container 1 is pressed upwardly, and is provided within thisimpression with a downwardly projecting well 5.

The outer container 1 is provided at its top with an opening 6, the saidopening being surrounded by a neck portion 7. A lid 8 is placed upon thesaid neck portion 7. The lid 8 is provided with a peripheral edge 9which sits around the neck 7, and, from the edge 9, a peripheral flange10 extends. The lid 8 is provided centrally with an upwardly projectingportion 1 I.

On the underside thereof, the lid 8 is provided with two downwardlyprojecting and encircling ridges 12 and 13 which form between them agroove for reception of a packing I4. A generally cylindrical formedinner container 15 is attached to the lid 8 by means of securing members(not shown), the upper, circular edge of the inner container 15 being insealing relationship with the packing 14 within the groove between thetwo annular ridges l2 and 13 on the underside of the lid 8.

Two connecting screws 16 and 17 are further arranged in the lid 8 tosecure two electrode holders l8 and 19 to the lid 8. The electrodeholders I8, 19 are formed of a suitable electrically conductive bandmaterial and support at the lower portion thereof the two electrodes20,21. Supply of current to the electrodes takes place via theconnecting screws 16, 17, in a manner not further illustrated, sincethis is known technique. A cover 39 is placed around the lid 8 as acurrent protection.

The electrodes 20, 21 are, as is apparent from FIG. 1, arranged withinthe steam chamber 27. In accordance with the invention, the innercontainer 15 is provided with two pockets 22, 23, by means of therespective partition walls 24, 25. In the partition wall 24, an orifice26 is provided, whereby the pocket 22 is in water-flow contact with thesteam chamber 27 in the inner container 15 and, in the same way, thepartition wall 25 is provided with an orifice 28. The inner container 15is provided in the bottom 29 thereof with an opening 30 which permitswater-flow contact between the pocket 22 and the well in the outercontainer 1, a corresponding opening 31 being also provided whichpermits water-flow contact between the pocket 23 and the well 5 in theouter container 1. In the bottom 29 an opening 32 is also provided whichgives direct contact between the well 5 and the steam chamber 27.

The lower portion of the inner container and thereby also the steamchamber 27 extends downwardly into the well 5, as is apparent fromFIG. 1. The purpose of this measure is explained herein below.

A disc-shaped member 33 is inserted into the central portion 11 of thelid 8. On the underside thereof, the disc-shaped member is provided witha plurality of guide wings 34 (see FIG. 2), and the disc 33 is disposedwithin the central portion of the lid 11 in that it is inserted formbelow and snapped past the thickened encircling portion 35 on the innerwall of the lid portion 11. The disc 33 has a central opening 36 which,on the underside of the disc, is surrounded by a short socket 37. Theupper portion 11 of the lid portion provides for an annular space 40between the disc 33 and the lid portion 11. This space 40 is open to theatmosphere in that an opening 41 is provided in the lid portion 11.

A recirculation element 44 is arranged in the inner container 15 andextends downwardly in the steam chamber 27 The said element is effectedas a conical tube piece which, at the lowest part thereof, has arelatively narrow opening 45 arranged immediately above the electrodes20, 21. The conical tube piece extends up to and around the socket 37 onthe disc 33 inserted in the lid portion 11. At the lowest part thereof,the conical tube piece has two guide surfaces 46, 47 (see FIG. 3). Therecirculation element 44 rests therewith upon the respective electrodes20, 21, and against the electrode holders 18,19. The electrode holders18,19 may preferably be pressed slightly apart one from the other bymeans of the guide surface 46, 47 on the recirculation element 44, sothat the recirculation element is thereby held in place by the springtension in the electrode holders 18,19.

The electrode air humidifier according to the invention operates in thefollowing manner. The outer container 1 is filled with water to thelevel 48. When the inner container 15, which is secured to the lid 8, isput in place, the water will have the same height within the steamchamber 27 as in the outer container 1 as a result of the water-flowcontact openings 30, 31, 32, 26, 28.

Current is then connected in manner known per se, and the electrodes 20,21 begin to heat the water within the steam chamber 27 in the innercontainer 15. The water in the steam chamber 27 begins to boil. In FIG.I, water level lines are drawn in the inner container, and it can beseen that the water level line within the recirculation element 44 isdrawn higher than the water level line in the steam chamber 27, whileboth these water level lines are below the water level line 48 in theouter container 1. It should naturally be remarked here that, in thesteam chamber 27 and in the recirculation element 44, no such definedwater level line will exist during boiling. On the other hand there ispresent a water-steam phase. The intention of the water level linesdrawn is merely to show that a greater force of water pressure ispresent in the recirculation element 44, so that the water circulationis as indicated by the arrow in the recirculation element 44, which isdue to the fact that the steam bubbles formed between the electrodes areretarded in the narrow opening 45 in the recirculation element 44, sothat the same concentrated bubble formation is not present within therecirculation element as is present outside this.

The pockets 22, 23 prevent pulsation to a great degree, since the waterhere is relatively hot, and is readily heated by the electrodes toboiling point. The water starts to boil,

whereby water is pressed out of the steam chamber due to the rapidlyincreasing steam pressure. When the steam pressure decreases the waterwill flow back from the pockets where the water has a temperature of C.The high temperature in the back flowing water reduces the non boilingperiod and the pulsation is therefore prevented or strongly reduced. Acertain controlled pulsation is ensured, however, in order to preventcollection of lime within the steam chamber, which might disturb theeffect of the electrodes and, to this purpose, a small opening 32 isprovided in the bottom of the steam chamber 27. Relatively cold waterfrom the outer container 1 can then flow into the steam chamber 27.

The steam developed is deflected by the guide blades 34 and is set inturbulent motion around the socket 37. At this point water is separatedwhich, as indicated, runs down along the inner walls in therecirculation element 44.

The steam thus passes through the socket 37 and into the space 40, andthereafter out through the opening 41, to the room in which the air isto be conditioned as regards humidity.

The water in the outer container 1 will gradually sink, and, when thewater level sinks so low that the electrodes 20, 21 are partiallyexposed, the effect of the electrodes will naturally decrease. A normalcourse of discharged amount of water per time unit is illustrated inFIG. 4 by means of the curve 50. The curve rises steeply to begin with,that is to say that the electrode air humidifier rapidly reaches itsmaximal distribution level. Gradually, as the water level sinks, thecurve slowly declines, as is apparent at the righthand side of FIG. 4.Such a curve course is undesirable since as long as the current ispresent in the water between the electrodes the electrodes are subjectto wearing, especially at the lower electrode ends. In

accordance with the invention it is the aim to provide a curve course asindicated by the curve 51, that is to say that the electrode airhumidifier stops sooner thus giving a more certain indication thatrefilling with water is required and resulting in a less wearance of theelectrodes.

In accordance with the invention, the contact between the water in theouter container I and the water in the steam chamber 27 is interruptedas soon as the water level is so low that the effect of the electrodesis reduced to a great degree, and this is achieved by means of theimpression 4, illustrated in FIG. 1, in the bottom of the outercontainer 1, with appurtenant well 5, wherein the inner container 15projects. As soon as the water level in the outer container 1 reachesthe level 52 indicated with the broken line, the contact between thegreater part of the water amount in the outer container 1 and the steamchamber 27 is interrupted, and the electrodes now heat and boil awayonly the water located in the well 5. As soon as the water level in thewell 5 reaches the level 53 (drawn with broken line in FIG. 1), thecurrent supply is naturally disconnected entirely and the discharge ofsteam is stopped completely.

Without departing from the scope of invention the pockets may bearranged on the outside of the inner container, the steam chamber thusoccupying the whole interior of the inner container.

I claim:

1. An electrode air humidifier comprising an outer liquid container aninner container defining a steam chamber within said outer containersteam generating electrodes suspended in spaced relation within saidsteam chamber a steam outlet at the top of the inner container a pocketchamber between the steam chamber and the outer container a liquidpassage between the steam chamber and the pocket chamber a liquidpassage between the pocket chamber and the outer container a tubeelement mounted vertically within the steam chamber above the electrodesand extending up to adjacent the steam outlet, the tube element having arestricted lower opening whereby the water droplets are returned throughthe tube element.

2. An electrode air humidifier as claimed in claim 1, and a directliquid passage between the steam chamber and the outer chamber.

3. An electrode air humidifier comprising an outer liquid container aninner container defining a steam chamber within said outer containersteam generating electrodes suspended in spaced relation within saidsteam chamber a steam outlet at the top of the inner container a tubeelement mounted vertically within the steam chamber above the electrodesand extending up to adjacent the steam outlet, the tube element having arestricted lower opening a partition in the inner container defining apocket chamber within the steam chamber a liquid passage between thesteam chamber and the pocket chamber a liquid passage between the pocketchamber and the outer container and means between the upper end of thetube element and the steam outlet for separating water droplets from thesteam whereby the water droplets are returned through the tube element.

4. An electrode air humidifier as claimed in claim 3, and a directliquid passage between the steam chamber and the outer container.

5. An electrode air humidifier as claimed in claim 3, and a 6. Anelectrode air humidifier as claimed in claim 5, and a direct liquidpassage between the steam chamber and the outer chamber.

7. An electrode air humidifier comprising an outer liquid container aninner container defining a steam camber within said outer containersteam generating electrodes suspended in spaced relation within saidsteam chamber a steam outlet at the top of the inner container a pocketchamber between the steam chamber and the outer container a liquidpassage between the steam chamber and the pocket chamber a liquidpassage between the pocket chamber and the outer container a tubeelement mounted vertically within the steam chamber above the electrodesand extending up to adjacent the steam outlet, the tube element having arestricted lower opening means between the upper end of the tube elementand the steam outlet for separating water droplets from the steamwhereby the water droplets are returned through the tube element and asteam guide member forming part of said separating means and imparting aturbulent effect to the steam and arranged in the steam outlet.

8. An electrode air humidifier as claimed in claim 7, and a directliquid passage between the steam chamber and the outer chamber.

9. An electrode air humidifier comprising an outer liquid container anannular partition defining a shallow well in the bottom of said outercontainer an inner container extending down in the well and defining asteam chamber within said outer container steam generating electrodessuspended in spaced relation within said steam chamber a steam outlet atthe top of the inner container a pocket chamber between the steamchamber and the outer container a liquid passage between the steamchamber and the pocket chamber and a liquid passage between the pocketchamber and the well. 10. An electrode air humidifier as claimed inclaim 9, and a direct liquid passage between the steam chamber and thewell. 11. An electrode air humidifier as claimed in claim 9, and a tubeelement mounted vertically within the steam chamber above the electrodesand extending up to adjacent the steam outlet, the tube element having arestricted lower opening, and means between the upper end of the tubeelement and the steam outlet for separating water droplets from thesteam whereby the water droplets are returned through the tube element.

12. An electrode air humidifier as claimed in claim 11, and a directliquid passage between the steam chamber and the well.

13. An electrode air humidifier as claimed in claim 11, and a steamguide member forming a part of said separating means and imparting aturbulent effect to the steam and arranged in the steam outlet.

14. An electrode air humidifier as claimed in claim 13, and

a direct liquid passage between the steam chamber and the well.

15. An electrode air humidifier comprising an outer liquid container anannular partition defining a shallow well in the bottom of said outercontainer an inner container extending down in the well and defining asteam chamber within said outer container steam generating electrodessuspended in spaced relation within said steam chamber a steam outlet atthe top of the inner container a partition in the inner containerdefining a pocket chamber within the steam chamber a liquid passagebetween the steam chamber and the pocket chamber and a liquid passagebetween the pocket chamber and the well.

16. An electrode air humidifier as claimed in claim 15, and

a direct liquid passage between the steam chamber and the well.

17. An electrode air humidifier comprising an outer liquid container anannular partition defining a shallow well in the bottom of said outercontainer an inner container extending down in the well anddefining asteam chamber within said outer container steam generating electrodessuspended in spaced relation within said steam chamber a steam outlet atthe top of the inner container a tube element mounted vertically withinthe steam chamber above the electrodes and extending up to adjacent thesteam outlet, the tube element having a restricted lower opening apartition in the inner container defining a pocket chamber within thesteam chamber a liquid passage between the steam chamber and the pocketchamber a liquid passage between the pocket chamber and the well andmeans between the upper end of the tube element and the steam outlet forseparating water droplets from the steam whereby the water droplets arereturned through the tube element.

18. An electrode air humidifier as claimed in claim 17, and

a direct liquid passage between the steam chamber and the well.

19. An electrode air humidifier as claimed in claim 17, and a steamguide member forming a part of said separating means and imparting aturbulent effect to the steam and arranged in the steam outlet.

20. An electrode air humidifier as claimed in claim 19, and a directliquid passage between the steam chamber and the well.

1. An electrode air humidifier comprising an outer liquid container aninner container defining a steam chamber within said outer containersteam generating electrodes suspended in spaced relation within saidsteam chamber a steam outlet at the top of the inner container a pocketchamber between the steam chamber and the outer container a liquidpassage between the steam chamber and the pocket chamber a liquidpassage between the pocket chamber and the outer container a tubeelement mounted vertically within the steam chamber above the electrodesand extending up to adjacent the steam outlet, the tube element having arestricted lower opening and means between the upper end of the tubeelement and the steam outlet for separating water droplets from thesteam whereby the water droplets are returned through the tube element.2. An electrode air humidifier as claimed in claim 1, and a directliquid passage between the steam chamber and the outer chamber.
 3. Anelectrode air humidifier comprising an outer liquid container an innercontainer defining a steam chamber within said outer container steamgenerating electrodes suspended in spaced relation within said steamchamber a steam outlet at the top of the inner container a tube elementmounted vertically within the steam chamber above the electrodes andextending up to adjacent the steam outlet, the tube element having arestricted lower opening a partition in the inner container defining apocket chamber within the steam chamber a liquid passage between thesteam chamber and the pocket chamber a liquid passage between the pocketchamber and the outer container and means between the upper end of thetube element and the steam outlet for separating water droplets from thesteam whereby the water droplets are returned through the tube element.4. An electrode air humidifier as claimed in claim 3, and a directliquid passage between the steam chamber and the outer container.
 5. Anelectrode air humidifier as claimed in claim 3, and a steam guide memberforming part of said separating means and imparting a turbulent effectto the steam and arranged in the steam outlet.
 6. An electrode airhumidifier as claimed in claim 5, and a direct liquid passage betweenthe steam chamber and the outer chamber.
 7. An electrode air humidifiercomprising an outer liquid container an inner container defining a steamcamber within said outer container steam generating electrodes suspendedin spaced relation within said steam chamber a steam outlet at the topof the inner container a pocket chamber between the steam chamber andthe outer container a liquid passage between the steam chamber and thepocket chamber a liquid passage between the pocket chamber and the outercontainer a tube element mounted vertically within the steam chamberabove the electrodes and extending up to adjacent thE steam outlet, thetube element having a restricted lower opening means between the upperend of the tube element and the steam outlet for separating waterdroplets from the steam whereby the water droplets are returned throughthe tube element and a steam guide member forming part of saidseparating means and imparting a turbulent effect to the steam andarranged in the steam outlet.
 8. An electrode air humidifier as claimedin claim 7, and a direct liquid passage between the steam chamber andthe outer chamber.
 9. An electrode air humidifier comprising an outerliquid container an annular partition defining a shallow well in thebottom of said outer container an inner container extending down in thewell and defining a steam chamber within said outer container steamgenerating electrodes suspended in spaced relation within said steamchamber a steam outlet at the top of the inner container a pocketchamber between the steam chamber and the outer container a liquidpassage between the steam chamber and the pocket chamber and a liquidpassage between the pocket chamber and the well.
 10. An electrode airhumidifier as claimed in claim 9, and a direct liquid passage betweenthe steam chamber and the well.
 11. An electrode air humidifier asclaimed in claim 9, and a tube element mounted vertically within thesteam chamber above the electrodes and extending up to adjacent thesteam outlet, the tube element having a restricted lower opening, andmeans between the upper end of the tube element and the steam outlet forseparating water droplets from the steam whereby the water droplets arereturned through the tube element.
 12. An electrode air humidifier asclaimed in claim 11, and a direct liquid passage between the steamchamber and the well.
 13. An electrode air humidifier as claimed inclaim 11, and a steam guide member forming a part of said separatingmeans and imparting a turbulent effect to the steam and arranged in thesteam outlet.
 14. An electrode air humidifier as claimed in claim 13,and a direct liquid passage between the steam chamber and the well. 15.An electrode air humidifier comprising an outer liquid container anannular partition defining a shallow well in the bottom of said outercontainer an inner container extending down in the well and defining asteam chamber within said outer container steam generating electrodessuspended in spaced relation within said steam chamber a steam outlet atthe top of the inner container a partition in the inner containerdefining a pocket chamber within the steam chamber a liquid passagebetween the steam chamber and the pocket chamber and a liquid passagebetween the pocket chamber and the well.
 16. An electrode air humidifieras claimed in claim 15, and a direct liquid passage between the steamchamber and the well.
 17. An electrode air humidifier comprising anouter liquid container an annular partition defining a shallow well inthe bottom of said outer container an inner container extending down inthe well and defining a steam chamber within said outer container steamgenerating electrodes suspended in spaced relation within said steamchamber a steam outlet at the top of the inner container a tube elementmounted vertically within the steam chamber above the electrodes andextending up to adjacent the steam outlet, the tube element having arestricted lower opening a partition in the inner container defining apocket chamber within the steam chamber a liquid passage between thesteam chamber and the pocket chamber a liquid passage between the pocketchamber and the well and means between the upper end of the tube elementand the steam outlet for separating water droplets from the steamwhereby the water droplets are returned through the tube element.
 18. Anelectrode air humidifier as claimed in claim 17, and a diRect liquidpassage between the steam chamber and the well.
 19. An electrode airhumidifier as claimed in claim 17, and a steam guide member forming apart of said separating means and imparting a turbulent effect to thesteam and arranged in the steam outlet.
 20. An electrode air humidifieras claimed in claim 19, and a direct liquid passage between the steamchamber and the well.